## Road Traffic Orientation: The Predominance of Right-Hand Traffic

### Overview

The direction of traffic flow varies around the world, with countries adopting either left-hand traffic (LHT) or right-hand traffic (RHT) rules. The rule specifies on which side of the road vehicles must drive. Globally, approximately 65% of the world’s population lives in countries with right-hand traffic regulations, making it the more common practice. This article delves into the history, distribution, and implications of driving on the right side of the road.

### Historical Development of Right-Hand Traffic

The preference for right-hand traffic dates back to ancient times. Historical evidence suggests that in past civilizations, such as those in ancient Rome, drivers and riders preferred to keep to the right. This practice may have stemmed from the fact that since most people are right-handed, riders would prefer to keep their right hand nearer to an opponent.

In the late 1700s, the trend towards right-hand traffic gained more structure, particularly with the increase in wagon traffic. In the United States, an increase in large freight wagons pulled by several pairs of horses called Conestoga wagons led to the formalization of the rule. These wagons did not have a driver’s seat, so the driver sat on the left rear horse, using their right hand to guide the team. It was easier for the driver to sit on the left rear horse and thus, traffic naturally flowed more smoothly when everyone drove on the right side, allowing the driver to have a better view of the passing wagons.

The move to adopt right-hand traffic was also politically influenced in some regions. For example, following the French Revolution, there was a conscious push to reject previous norms, including road practices. As Napoleon conquered parts of Europe, his influence helped spread right-hand driving further.

### Legal Institution of Right-Hand Traffic

In many countries, the switch to right-hand traffic was formalized by law. The United States standardized its traffic rules, including right-hand driving, in the early 20th century, with most states adopting these rules uniformly by the 1920s. Similarly, in Europe, many countries gradually shifted from left-hand to right-hand traffic. A notable moment was on September 3, 1967, known as "Dagen H" ("H Day"), when Sweden switched from left-hand traffic to right-hand traffic, an event that required extensive preparation and was remarkably executed without major incidents.

### Current Global Distribution

Today, right-hand traffic is the norm in most of the Americas, China, Russia, and Europe. Countries that were part of the British Empire or are still part of the Commonwealth, such as the UK, India, Australia, and some African countries, predominantly use left-hand traffic.

### Implications and Safety Considerations

The orientation of traffic affects various aspects of road design and vehicle manufacturing. Vehicles in right-hand traffic countries have the steering wheel on the left, optimizing driver visibility of road markings and oncoming traffic. Traffic signs and signals are also positioned in accordance with the direction of traffic, which can significantly impact safety.

Studies have sought to determine whether there is a safety difference between left-hand traffic and right-hand traffic systems, though results are inconclusive. However, the transition period from one system to another is notably hazardous as drivers adjust to the new norm.

### Conclusion

Driving on the right side of the road is a practice rooted in historical, cultural, and political contexts and has evolved to accommodate the growth of road traffic systems. This method of traffic orientation supports the infrastructure and vehicular design in many parts of the world, enhancing the flow and safety of road transportation. As global interaction increases, understanding and navigating these differences remains crucial for travelers and international road safety efforts.